[src/trunk]: src/external/cddl/osnet/dist/uts/common/fs/zfs Teach zfs bdevsw ...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/21a480f7e72d
branches:  trunk
changeset: 745310:21a480f7e72d
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Fri Feb 28 03:52:26 2020 +0000

description:
Teach zfs bdevsw to do b_psize.

This is needed, among other things, to swap on zvols.

Attempting to swap on zvols currently deadlocks but that's a separate
issue that needs to be fixed too!

diffstat:

 external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c |  25 +++++++++++++++++-
 1 files changed, 24 insertions(+), 1 deletions(-)

diffs (42 lines):

diff -r 0bfe27574f86 -r 21a480f7e72d external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c
--- a/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c    Thu Feb 27 23:15:34 2020 +0000
+++ b/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ioctl.c    Fri Feb 28 03:52:26 2020 +0000
@@ -7062,6 +7062,29 @@
        (void) zvol_strategy(bp);
 }
 
+static int
+nb_zvol_psize(dev_t dev)
+{
+       minor_t minor = getminor(dev);
+       off_t nbytes;
+       unsigned bytespersector;
+
+       if (minor == 0)         /* /dev/zfs */
+               return -1;
+
+       if (zvol_ioctl(dev, DIOCGMEDIASIZE, (intptr_t)&nbytes, 0,
+               NOCRED, NULL))
+               return -1;
+       if (zvol_ioctl(dev, DIOCGSECTORSIZE, (intptr_t)&bytespersector, 0,
+               NOCRED, NULL))
+               return -1;
+       if (bytespersector == 0) /* paranoia */
+               return -1;
+       if (nbytes/bytespersector > INT_MAX) /* paranoia */
+               return -1;
+       return nbytes/bytespersector;
+}
+
 static const struct fileops zfs_fileops = {
        .fo_name = "zfs",
        .fo_read = fbadop_read,
@@ -7081,7 +7104,7 @@
        .d_strategy = nb_zvol_strategy,
        .d_ioctl = nb_zfsdev_ioctl,
        .d_dump = nodump,
-       .d_psize = nosize,
+       .d_psize = nb_zvol_psize,
        .d_flag = D_DISK | D_MPSAFE
 };